STMicroelectronics STM32L151R6T6TR

Overview

STM32L151R6T6TR from STMicroelectronics is an ultra-low-power 32-bit ARM® Cortex®-M3 microcontroller featuring 128 KB Flash, 32 KB SRAM, 4 KB EEPROM with ECC, 12-bit ADC (1 Msps, 24 channels), and dual 12-bit DACs - deployed in battery-powered IoT sensors and portable medical devices requiring sub-µA standby operation.

For engineers reviewing the STM32L151R6T6TR datasheet, STM32L151R6T6TR pinout, STM32L151R6T6TR application, or STM32L151R6T6TR equivalent, key selection criteria include verified 0.28 µA Standby current, 10.9 µA Low-power Run mode, USB 2.0 interface with internal 48 MHz PLL, and support for capacitive touch sensing across up to 20 channels.

Technical Context

The STM32L151R6T6TR integrates a Cortex-M3 core operating from 32 kHz to 32 MHz, with dynamic voltage scaling enabling multiple low-power operating modes - including Stop mode (0.44 µA) and Standby mode (0.28 µA) - each with configurable wakeup sources and RTC retention. Its memory subsystem includes ECC-protected Flash and true EEPROM, ensuring data integrity in harsh environments.

Peripherals are optimized for energy efficiency: the 12-bit ADC supports hardware oversampling and analog watchdogs; dual DACs provide buffered outputs; two ultra-low-power comparators enable windowed threshold detection with wake-up capability; and the USB interface uses an internal PLL eliminating external crystal requirements.

Key Specifications

Pinout & Package

LQFP64 package: 64-pin low-profile quad flat package, 10 × 10 mm body, 0.5 mm pitch, exposed pad optional for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-power MCU applications.

Compared with STM32L151R6T6TR, STM32L051R8T6 offers lower cost and smaller die but sacrifices USB, EEPROM, and analog feature depth; STM32L431RCI6 delivers higher compute throughput and USB OTG at the expense of increased power consumption and absence of true EEPROM.

Availability

STM32L151R6T6TR is available at Aetrix Electronics and suitable for wearable health monitors, smart utility meters, wireless sensor nodes, and portable diagnostic devices requiring stable component supply across multi-year production cycles.

Supply support for STM32L151R6T6TR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, and MEMS sensors for industrial, automotive, and consumer markets.

The STM32L1 series targets ultra-low-power embedded applications demanding extended battery life, robust memory integrity, and rich analog integration - specifically engineered for IoT edge nodes and portable medical electronics.

FAQ

What is the maximum operating frequency and corresponding power consumption in Run mode?

The STM32L151R6T6TR operates up to 32 MHz with dynamic voltage scaling. At 32 MHz and 3.3 V, typical Run mode current is 185 µA/MHz (≈5.92 mA total), measured with code executing from Flash and peripherals idle. This value scales linearly down to 10.9 µA in Low-power Run mode at 32 kHz.

Does this MCU support USB device functionality without external crystal?

Yes. The STM32L151R6T6TR integrates a 48 MHz PLL fed by its internal 16 MHz HSI oscillator, enabling full-speed USB 2.0 device operation without an external crystal. The USB transceiver is fully embedded, requiring only standard D+/D− routing and 1.5 kΩ pull-up on D+ for enumeration.

How is EEPROM implemented, and what is its endurance rating?

This device features 4 KB of true EEPROM emulated in Flash with hardware ECC and wear-leveling. ST specifies 400,000 write/erase cycles and 20-year data retention at 55°C - validated per JEDEC JESD22-A117. No software emulation layer is required; it behaves as standard byte-addressable EEPROM.

What are the wakeup sources available from Standby mode?

Standby mode supports wakeup from three dedicated pins (WKUP1–WKUP3), RTC alarm/event, tamper event, or IWDG reset. All three WKUP pins retain their function with 0.28 µA quiescent current, and each can be configured with rising/falling edge detection independent of other system clocks.